by Tom Vanden Brook, USA TODAY

by Tom Vanden Brook, USA TODAY

JERUSALEM - The United States and Israel share a united front against Iran, and the U.S. commitment to defending its longtime ally in the Middle East remains unbreakable, Defense Secretary Chuck Hagel and Israeli Prime Minister Benjamin Netanyahu said Tuesday.

Hagel is traveling in the Middle East this week to meet with defense officials to formalize an agreement to sell Israel $10 billion in arms that could be used to confront Iran. They include advanced radars, aerial refueling tankers and missiles that can destroy air defenses.

"This is a difficult and dangerous time; this is a time when friends and allies must remain close, closer than ever," Hagel said.

Netanyahu restated Israel's vow to strike Iran before it attains a nuclear weapon, a stance Hagel has said has U.S. support.

"This is a challenge that Israel cannot accept, and as you and President Obama have repeatedly said, Israel must be able to defend itself by itself against any threat," Netanyahu said.